This application claims the benefit of Korean Patent Application No. 2002-33086 filed on Jun. 14, 2002, in the Korean Industrial Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to microwave ovens, and more particularly, to a microwave oven which evenly cooks food seated on a cooking tray in a cooking cavity of the microwave oven, even where the cooking tray is not rotated.
2. Description of the Related Art
Generally, a microwave oven is an electrically operated oven, which heats and/or cooks food laid in its cooking cavity using high-frequency electromagnetic waves. The high-frequency electromagnetic waves are generated by oscillation of a magnetron installed in a machine room of the microwave oven. That is, during a cooking operation, the magnetron installed in the machine room irradiates the high-frequency electromagnetic waves (xe2x80x9cmicrowavesxe2x80x9d) through the cooking cavity. The microwaves penetrate the food so as to repeatedly change the molecular arrangement of moisture laden in the food, causing the molecules of the moisture to vibrate and generate frictional heat within the food to cook the food. Such a microwave oven is typically provided with both a wave guide and a wave dispersing unit which guide the microwaves from the magnetron and disperse the microwaves to the food seated in the cooking cavity. The microwave oven also has a turntable-type cooking tray which seats food thereon and is rotated at a low speed during the cooking operation.
FIG. 1 shows the construction of a conventional microwave oven. As shown in the drawing, the conventional microwave oven comprises a cabinet 1 which forms the outer appearance of the microwave oven, and a cooking cavity 2 which is defined inside the cabinet 1 to form a cooking chamber to cook food therein. A machine room 3 is defined inside the cabinet 1 at a position beside the cooking cavity 2 such that the machine room 3 is partitioned from the cavity 2. The machine room 3 receives a variety of devices used to generate microwaves.
A cooking tray 4 is set on a bottom of the cooking cavity 2 and seats food thereon. The cooking tray 4 is rotated by a tray motor 5 at a predetermined speed. A tray guide 6, with a plurality of rollers 7, is set under the cooking tray 4 to rotatably support the tray 4 on the bottom of the cooking cavity 2.
The devices installed in the machine room 3 include a magnetron 8 which generates the microwaves, and a wave guide 9 which guides the microwaves from the magnetron 8 into the cooking cavity 2. The magnetron 8 is installed at an inlet of the wave guide 9, while a wave dispersing unit 10 is provided at an outlet of the wave guide 9. The wave dispersing unit 10 disperses the microwaves, guided thereto under the guide of the wave guide 9, into the cooking cavity 2.
During an operation of the microwave oven, the microwaves generated from the magnetron 8 are transmitted into the cooking cavity 2 through the wave guide 9. In addition, the cooking tray 4 loaded with food xe2x80x9cFxe2x80x9d thereon is rotated at a low speed under the guide of the tray guide 6 by a rotating force of the tray motor 5. The food xe2x80x9cFxe2x80x9d laid on the cooking tray 4 is heated and cooked by the microwaves.
However, since the wave guide 9 is placed at a top wall of the cooking cavity 2, the wave dispersing unit 10 installed at the outlet of the wave guide 9 is limited in its operational effect. That is, where the microwaves from the magnetron 8 reach the outlet of the wave guide 9, the wave dispersing unit 10 only disperses the microwaves downward from the outlet of the wave guide 9 into the cooking cavity 2. Accordingly, the microwaves are not effectively transmitted to a lower and side parts of the food xe2x80x9cFxe2x80x9d laid on the cooking tray 4.
Where the size of the food xe2x80x9cFxe2x80x9d to be cooked is large, it may inhibit a proper rotation of the cooking tray 4. In such a case, the cooking operation must be performed without rotating the cooking tray 4. Therefore, the microwaves cannot be evenly radiated to the entire parts of the food xe2x80x9cF.xe2x80x9d Furthermore, it is almost impossible to transmit an effective quantity of the microwaves to the lower part of the food xe2x80x9cF.xe2x80x9d The microwave oven, having such a wave dispersing unit at the top of the cooking cavity 2, thus undesirably lengthens a cooking time and fails to accomplish a desired cooking result.
Additionally, such an arrangement of the wave dispersing unit 10 at the top of the cooking cavity 2 does not allow a user outside the microwave oven to see a rotation of the wave dispersing unit 10. Therefore, the user cannot visually confirm the rotating action of the wave dispersing unit 10. Accordingly, an operation of the conventional microwave oven does not provide a sense of beauty which is expected to be enhanced by a visual confirmation of the rotation of the wave dispersing unit 10 inside the cooking cavity 2. This degrades market competitiveness of the conventional microwave oven.
Accordingly, it is an object of the present invention to provide a microwave oven which evenly irradiates microwaves to the entire parts of food seated in its cooking cavity.
Another object of the present invention is to provide a microwave oven, which effectively cooks large-sized food even though the food inhibits a proper rotation of a cooking tray in the cooking cavity, and which improves the appearance of the cooking cavity, thus enhancing the market competitiveness of the microwave ovens.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
To achieve the above and other objects of the present invention, there is provided a microwave oven comprising a cabinet which forms an outer appearance of the oven, a cooking cavity defined inside the cabinet, a machine room defined inside the cabinet and partitioned from the cooking cavity, and a side wave dispersing unit which is provided at a sidewall of the cooking cavity and disperses microwaves into the cooking cavity.
The microwave oven further comprises a magnetron which is installed in the machine room and generates the microwaves. The machine room is partitioned from the cooking cavity by a second sidewall of the cooking cavity, and the side wave dispersing unit is provided at the sidewall opposite from the second sidewall of the cooking cavity.
The microwave oven further comprises a cover which is installed in front of the side wave dispersing unit and transmits the microwaves to/from the side wave dispersing unit and the cooking cavity.
The sidewall of the cooking cavity includes a recess which seats the side wave dispersing unit therein.
The microwave oven further comprises an upper wave dispersing unit which is provided at an upper portion of the cooking cavity and downwardly disperses the microwaves from the upper portion to a lower portion of the cooking cavity, and a wave guide which extends from an upper portion of the machine room to the upper portion of the cooking cavity and guides the microwaves to the cooking cavity. The upper wave dispersing unit is installed at an outlet of the wave guide.